Thanks for the input. We ran the tests last spring semester and I've posted some preliminary results on our website (rundown graphs). I'll try to upgrade the results to include the final report and more graphs.
In addition to rundown tests, we did subjective, "What can you see with this light, how far away, and how focused is it?"
Most of the lights we tested would be more than adequate for tactical lights. We did discovered some interesting things.
1- Basically the Xenon bulb lights (CR123 batteries) last about 60 minutes and the light intensity decreases essentially linearly with use. I.e. after 30 minutes of continuous use the light intensity will be about half what it was when you first turn it on.
2- LED lights are no where near as bright as Xenon lights, but they are still bright enough to produce that blinding effect.
3- LED lights run time is over twice as long as Xenon bulb lights and the beam intensity is nearly constant instead of constantly decaying.
4- Xenon bulbs "render" colors much better. That means that you see colors better, they show up brighter and richer.
5- The LED lights we tested had a uniform beam. I.e. didn't have dark spots, rings, or bands.
6- The brightest LED light was the Inova T3, but the Inova has no gripping surfaces which makes it hard to hold especially under less than ideal condtitions.
7- When a Xenon light runs down, it goes out, period. When an LED light runs down, it can still produce a useable light for many hours. I left one on continuously for 12 hours and could still see decently with it even though it was no where near tactical intensity.
8- Xenon lights are not good "search" lights, i.e. routine looking for things, because they only last 60 minutes.
9- Xenon lights are much better for threat searching because the beam is brighter and the color rending discloses color detail better.
10- For long range, there is no subsitute for power. The Streamlight Ultra Stinger (rechargeable) and the Streamlight TL3 (3 CR 123 batteries) were unsurpassed in projecting light over longer ranges. The TL3 is a fairly compact light and a high performer, but it does use a Zenon bulb and CR123 batts, so beam intensity will decrease with use. The Ultra Stinger uses a nicad battery and has a more consistent beam output with use, runs about 60 minutes contiunous, but it dies in a hurry - like from a pretty bright light to completely out in three minutes.
11- the Surefire L2 (Luxeon LED) and the Surefire Aviator (Xenon with three low power LEDs) lasted about 20 minutes before they became so hot that they started flashing (overheating). They were so hot you could hardly hold them in your hand. That's not good.
Here's a link to some preliminary info and some of the flashlights:
http://chattanoogastate.edu/engineering ... 20rwrt.pdf
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